อรุณศิริ ทิพฤกษ์. Simulation and Comparison of Energy Consumption for Air Separation Technologies. Master's Degree(Chemical Engineering). King Mongkut's University of Technology Thonburi. KMUTT Library. : King Mongkut's University of Technology Thonburi, 2010.
Simulation and Comparison of Energy Consumption for Air Separation Technologies
Abstract:
Air separation technologies have been developed for supplying high purity of oxygen
which is a major part of the capital cost and operating cost of power plants and
industrial processes using oxy-combustion and pre-combustion gasification of fuels.
The process behaviors of the air separation technologies have been widely studied
individually. However, the study of energy consumption and the comparison of
technologies have not been focused; therefore it might be worthwhile to develop the
steady state models of the air separation technologies to compare their required energy,
the production rate, and the product purity. In this study, pressure swing adsorption
(PSA), vacuum swing adsorption (VSA), cryogenic and Ba0.5sSr0.5Co0.8sFe0.2O 3-8 (BSCF)
membrane were modeled using input data from the available literatures. Initially, Aspen
Plus was a simulator used to develop the steady state model of cryogenic process while
BSCF membrane was developed using MATLAB. Additionally, Aspen Adsim was used
to model the cyclic steady state of both PSA and VSA. After that, some parameters had
to be adjusted to match the essential parameters and the pressure profile obtained from
the experimental data. For both PSA and VSA adsorption processes, the pressure
profiles and the product purity from the simulation models agreed satisfactorily with the
experimental results, while the flow quantities and oxygen recovery were not close to
those of the experiment. The results of BSCF membrane gave a good fit with the
experiment. However, the convergence of the simulation was limited at low oxygen
partial pressure, 0-0.129 atm. Therefore, a range of 0.13-1 atm was the oxygen partial
pressure which could be converted to obtain the verified permeation flux. The suitable
technique for each process depended on the requirement of the product quality and
quantity. Cryogenic process was favored at high oxygen production rates and purity
with low energy consumption, while BSCF membrane, VSA, and PSA were favored at
lower oxygen production, respectively. The results also showed that BSCF membrane
technology can produce oxygen with the highest purity at the lowest oxygen production.
Besides, this technology required the lowest energy consumption and had high potential
for improvement. Thus, this technology can be an alternative technology for air
separation process.